The present invention relates to a cooking utensil for cooking various articles of food. The invention is particularly useful with respect to the cooking utensil described in WO 9103972 published Apr. 14, 1991, and is therefore described below with respect to that type of cooking utensil.
WO 9103972 discloses a cooking utensil comprising a container for receiving articles of food to be cooked, and a lid attachable to the container and defining therewith an annular water reservoir surrounding the open top of the container for receiving a liquid. The liquid seals the interior of the container against the entry of air from the atmosphere and also filter out any smoke or other particles produced in the container during the cooking. Since the liquid seal prevents the entry of air into the container, the food articles to be cooked, as well as additive material (e.g., wood chips, or other substances, to provide color flavor or aroma) introduced at the bottom of the container, may be heated to a very high temperature without ignition. The high temperature within the container causes the food articles to be cooked in a relative short time. It also causes the volatile ingredients of the additive material to be readily evaporated, thereby adding color, flavor and/or aroma to the food product.
However, in the cooking utensil described in that document the lid must be locked to the container, and the interior of the container should be substantially cooled and depressurized to near atmospheric pressure, before the lid is removed; otherwise, removal of the lid while the interior of the container is still very hot, and under a relatively high vacuum, may draw a large quantity of the liquid from the annular reservoir into the interior of the container, instantly vaporizing the liquid and producing a high pressure which could be dangerous. For this reason, the cooking utensil described in that document includes a locking device for locking the lid to the container, and one version also includes a valve to permit only a small quantity of the water to be introduced into the reservoir during the cooling process